A Rare Case of Subarachnoid Hemorrhage caused by Ruptured Venous Varix Due to Dural Arteriovenous Fistula at the Foramen Magnum Fed Solely by the Ascending Pharyngeal Artery

Abstract

Dural arteriovenous fistula (D-AVF) at the foramen magnum is an extremely rare disease entity. It produces venous hypertension, and can lead to progressive cervical myelopathy thereafter. On the other hand, the venous hypertension may lead to formation of a venous varix, and it can rarely result in an abrupt onset of subarachnoid hemorrhage (SAH) when the venous varix is ruptured. The diagnosis of D-AVF at the foramen magnum as a cause of SAH may be difficult due to its low incidence. Furthermore, when the D-AVF is fed solely by the ascending pharyngeal artery (APA), it may be missed if the external carotid angiography is not performed. The outcome could be fatal if the fistula is unrecognized. Herein, we report on a rare case of SAH caused by ruptured venous varix due to D-AVF at the foramen magnum fed solely by the APA. A review of relevant literatures is provided, and the treatment modalities and outcomes are also discussed.

Early rebleeding of a foramen magnum dural arteriovenous fistula: A case report and review of the literature

“…We searched relevant published articles regarding FM-DAVF with SAH. We found overall 11 corresponding cases among 5 articles ( Table 1 ) [1 , [3] , [4] – 5 , 8] . 5 patients had an arterial supply from the ascending pharyngeal artery.…”

“…CCJ-AVF may result in SAH and congestive myelopathy. A diagnosis of CCJ-AVF may be difficult because of its low incidence and variable clinical features [1 , 4] .…”

“…2017 [4] 69/F SAH VA MV, IPS Direct surgery Motebejane and Choi 2017 [3] 53/M SAH APA MV IVR with NBCA 42/M SAH APA, VA MV IVR with NBCA 51/M SAH APA, VA MV, JB IVR with NBCA Kim et al. 2018 [1] 48/M SAH APA VP, SS IVR with Onyx APA, ascending pharyngeal artery; COS, confluence of sinuses; F, female; FM-DAVF, foramen magnum dural arteriovenous fistula; IPS, inferior petrosal sinus; IVR, interventional radiology; JB, jugular bulb; M, male; MV, medullary vein; NBCA, n-butyl cyanoacrylate glue; OA, occipital artery; SAH, subarachnoid hemorrhage; SS, sigmoid sinus; StS, straight sinus; VA, vertebral artery; VP, venous plexus. …”

“…Foramen magnum dural arteriovenous fistula (FM-DAVF) is a subset of craniocervical junction arteriovenous fistula (CCJ-AVF) with the fistulous point at the foramen magnum. Few relevant reports exist regarding FM-DAVF [1] . CCJ-AVF is rare vascular malformation that may result in subarachnoid hemorrhage (SAH), congestive myelopathy, and brainstem dysfunction [2] .…”

Medullary hemorrhage caused by foramen magnum dural arteriovenous fistula successfully obliterated using combination of endovascular and surgical treatments: A case report and literature review

“…We reviewed the published case reports which have sufficient clinical description and clearly demonstrated figures of foramen magnum DAVFs. [39131620212223242526272829303132333435] The collected data in this review include demographic data (i.e., gender and age of patient), presenting symptoms, the findings of image studies, arterial feeders of the fistula, location of the draining veins, the presence of venous varix, treatment of the fistula, and neurological outcomes following treatment [Table 1]. From the literature review, there were 27 cases, including our case, with 27 foramen magnum DAVFs.…”